A prominent Long Island restaurateur arranged and paid for several vacation trips for Nassau County Executive Edward Mangano and a top Oyster Bay Town official, a Newsday investigation has found.

Harendra Singh -- a politically connected Bethpage-based businessman -- coordinated travel itineraries and payment for trips for Mangano, members of the Mangano family and Oyster Bay Deputy Town Attorney Frederick Mei, according to emails, invoices and other documents obtained by Newsday.

Singh's employees typically handled the arrangements for trips -- to the U.S. Virgin Islands, the Turks and Caicos, India and South Korea -- the records show, but Singh was often personally involved. A July 18, 2013, email from Singh to his travel agent includes the following instruction: "Please send a pre paid car for Mangano as he is important."

The records do not indicate whether Mangano ever reimbursed Singh, or whether he actually went on the trips. Mangano did not respond to requests for comment. His spokesman and his attorney declined to answer questions, including whether Mangano took the trips.

State and county laws prohibit public officials from accepting gifts from individuals or entities doing business with their government agencies. Such laws are in place to prevent people from influencing how public contracts are awarded.

Singh, whose sprawling business interests include restaurants, concession stands and a catering service, has landed several lucrative contracts from Nassau County and Oyster Bay.

Federal authorities subpoenaed Singh's business records last year but have not questioned him specifically about the trips, said Joseph Conway, a Mineola criminal defense attorney who has represented Singh in the past. Conway said he helped Singh with the subpoenas but is not acting as his attorney "until he gets arrested or something, if in fact that's going to happen."

Conway said he does not know what the focus of the investigation is but added that Singh is cooperating with federal investigators.

A spokeswoman for the Eastern District of the U.S. attorney's office declined to comment.

The records obtained by Newsday show Singh and his employees worked with Travel Time and Tours, a Hicksville travel agency, to schedule two trips for Mangano and three of his family members. Those trips overlapped with ones Singh planned for himself and members of his own family.

The first trip, in July 2012, was scheduled for St. John in the U.S. Virgin Islands. The second trip, scheduled for July 2013, was for the Turks and Caicos, where Singh arranged for the Manganos to stay in a two-bedroom oceanfront suite for $4,961.

An email dated June 3, 2013, sent by a travel agent to Singh, said the total cost of a trip to the Turks and Caicos for Singh, Singh's guests and the Manganos was $17,498.

A source familiar with the situation said the 2012 trip might have been canceled but that Mangano and his family went on the second trip to the Turks and Caicos.

Brian Nevin, Mangano's spokesman, declined to answer questions for this story and did not provide Newsday with Mangano's calendar for the days the trips were scheduled. Nevin referred questions to Mangano's attorney, Kevin Keating.

"There is absolutely no story here," said Keating, a criminal defense attorney in Garden City. "The Manganos and the Singhs have been friends for many, many years, lifelong friends."

Like Keating, Conway said Mangano and Singh were close friends, and their friendship included vacationing together and splitting the costs. "It was not unusual for both of them to book and make payments to or for each other," Conway said.

Mangano's financial disclosure forms do not include any gifts in the years that coincide with the Singh trips.

Newsday obtained the travel records and emails from a source who provided them to the newspaper on the condition of anonymity. Reporters verified the authenticity of the travel documents used for this story. The source who provided the records to Newsday said the same documents were also given to federal investigators.

Besides the Mangano trips, the records show that Singh employees Robert Lobo and Jay Jadeja coordinated and arranged payment for at least three trips taken by Mei, the Town of Oyster Bay's deputy attorney. The trips -- one to India in October 2010, one to Seoul, South Korea, in July 2012 and another to India in December 2012 -- are mentioned on Mei's own Facebook page.

The records do not indicate whether Mei reimbursed Singh for the trips. Mei did not respond to calls for comment.

Lobo, who is listed in an online profile as the financial controller for Singh Hospitality Group, confirmed in an interview that Singh "asked me to take care of some payments" concerning the trips.

"I'm just an employee of Mr. Singh," Lobo said. "I have to do what my boss tells me."

The emails obtained by Newsday show that Mei was deeply involved in negotiating concession agreements between the Town of Oyster Bay and Singh, and also in Singh's efforts to secure several loans and a line of credit. An Oyster Bay Town resolution shows that the board approved giving Singh three additional concessions at town beaches at Centre Island, Stehli Beach and Tappen Beach in December 2012, the same year Mei took two trips paid for by Singh.

Singh's businesses fell behind on their concession payments to Oyster Bay, and town officials have said he owed them roughly $75,000 at the end of July.

Town officials provided portions of the concession agreements with Singh at Tobay Beach and the golf course in response to a Freedom of Information request filed by Newsday, but they have withheld parts of the agreements without explanation.

Oyster Bay's outside counsel, Jonathan Pickhardt, a partner in the Manhattan law firm Quinn Emanuel Urquhart & Sullivan, said Mei is still employed by the town but that his employment status is "under review." He declined to elaborate.

Pickhardt said Oyster Bay Supervisor John Venditto and Town Attorney Leonard Genova had not been aware that Singh paid for Mei's trips. Venditto did not return calls for comment.

Singh also paid for at least four car service trips for Genova and Genova's son, the records show. Those trips occurred in April 2011 and in February and July 2013.

Car service invoices billed to Singh's account show Camelot Specialty Limos of New Hyde Park picked up Genova's son on April 24, 2011, at the family's home and drove him to Columbia University. Then on Feb. 6, 2013, the same company picked up Genova at the Oyster Bay Department of Public Works and drove him to Amsterdam Avenue and West 80th Street. On July 26, 2013, the car service picked up Genova at his home, drove him to NewYork-Presbyterian Hospital/Columbia University Medical Center, and then drove him home again.

Genova, who is a member of the town's ethics board, declined to comment. Pickhardt said Genova ultimately wrote a check to the car service for $1,650 in October 2013 to pay for the trips. Pickhardt said Genova delayed paying for the trips because he had been preoccupied with his ill wife, who died in January of uterine cancer.

He arrived in the United States in 1979 from India and opened his first A & W Restaurant in Bethpage, Mangano's hometown, in 1988. He added other restaurants to his portfolio, including his flagship restaurant, H.R. Singleton's in Hicksville.

As he succeeded in business, Singh forged close ties with Oyster Bay and Nassau County officials.

Oyster Bay awarded its first concession agreement, to provide food and beverage services at the town golf course, to Singh in 2000. In 2005, the town exercised a 10-year option to renew the golf concession and entered into a 20-year agreement with another Singh company at Tobay Beach. In 2008, the town extended both agreements by 20 years. Last year, the town again extended the concession agreements by 20 years, to 2070 for the golf course and to 2065 for Tobay Beach.

Singh also had an outside business relationship with Frederick Ippolito, the town's building and planning commissioner. Newsday reported in February 2013 that Singh had purchased from Ippolito Christiano's, the Syosset restaurant said to be the inspiration behind a Billy Joel song.

Singh had said he would give the restaurant a makeover but instead closed it in February 2014. A year later, Singh said he was walking away from the restaurant.

Ippolito faced tax problems over Christiano's before Singh took the restaurant off his hands. A 2006 tax audit found the restaurant owed $122,608 plus interest for outstanding use and sales taxes, and Ippolito argued that the debt should go to his wife, and not him. Last year a state appellate court ruled Ippolito must pay his portion of the debt, which is now more than $146,000.

In March, federal prosecutors charged Ippolito with tax evasion for allegedly failing to report $2 million of consulting fees from Carlo Lizza & Sons Paving Inc., a company that has had multimillion-dollar contracts with Oyster Bay and Nassau County, and with a Lizza family member. The fees were collected from 2008 through 2013, according to the indictment. Ippolito pleaded not guilty in U.S. District Court in Central Islip.

Singh also has close personal and professional ties to Mangano, whose wife and son have both worked for Singh's companies. When Mangano was sworn in for his second term as county executive last year, Singh was one of the few private citizens on stage with him.

Records show Mangano's campaign paid Singh's companies at least $75,000 for food, fundraisers and office space rented for campaign headquarters. After superstorm Sandy hit Long Island in October 2012, Nassau County paid a Singh company, Raj & Raj Realty, $238,200 through a no-bid "emergency purchase order" for hot meals for public officials.

Politicians from both Nassau County and Oyster Bay have supported Singh's father's nonprofit organization, The Raj & Rajeshwari Foundation, which helps fund a hospital and feeding centers in India. The foundation holds summer galas at the Woodlands, the restaurant Singh runs at the town golf course.

Mangano and Venditto were special guest speakers at four of the foundation's last five fundraisers. Since 2006, Venditto's campaign has paid $12,500 to the foundation in donations, sponsorship and for journal ads, campaign finance records show.

The dinners, which last year cost $175 per plate, have honored local residents and political figures. Venditto, Ippolito, Nassau County chief deputy county executive Rob Walker and Linda Mangano, the county executive's wife, are among those honored by the foundation.